Currently, due to the influence of uncertain factors such as the standard operating procedures (SOPs) of production line environments, product processes or production lines, in the processes such as the assembly or detection of electronic products, environmental foreign substances can easily enter, for instance, a backlight module, a space between layers of a display panel (foreign substances in films), or a space between the backlight module and the display panel (foreign substances on the outside of films). Due to the foreign substances, poor image quality such as white spots and white dirt of the display panel tends to occur after product transport or mechanical reliability test. For instance, as for a touch panel product, foreign substances with the size of a dozen microns will adhere to the touch panel, and the display panel may have poor image quality such as severe white dirt and white spots after drop test, vibration test and other actions, so the product quality and yield can be severely affected.
Currently, the interception of foreign substances mainly relies on the measures such as environmental control in dust-free workshops and image quality inspection by the quality department before shipment. In actual production, considering the protection of electronic components on a chip on film (COF) and/or a printed circuit board (PCB), in the processes of production, inspection and shipment of electronic products, one side of a display panel bonded with a PCB is placed upwards, and partial foreign substances on the inside and outside of films fall down and are gathered on an opposite side of one side of the display panel bonded with the PCB at this stage, for instance, the foreign substances fall into gaps between the display panel and a frame of a backlight module, and hence cannot be effectively detected; and after the assembling the electronic products into a complete set, one side of the display panel bonded with the PCB is placed downwards, and foreign substances will fall onto active area from the gaps, resulting in display distortion, poor quality and the like and reducing the product yield.